diff --git a/Include/opcode.h b/Include/opcode.h
index ea484c5..4f52c5f 100644
--- a/Include/opcode.h
+++ b/Include/opcode.h
@@ -106,6 +106,7 @@ extern "C" {
 #define LOAD_FAST               124
 #define STORE_FAST              125
 #define DELETE_FAST             126
+#define GEN_START               129
 #define RAISE_VARARGS           130
 #define CALL_FUNCTION           131
 #define MAKE_FUNCTION           132